Discharge mechanism



Aue- 31, T9261' G. W. SAATHOFF DISCHARGE MECHANISM Filed Nov. 24', 1924 3 Sheets-Sheet 1 Aug. 3l, 1926.

G. W. SAATHOFF DISCHARGE MEQHANISM Filed Nov. 24, 1924 5 Sheets-Sheet Patented Aug. 31, 1926i.

UN'TED sra'rss Parana ortica encuen-W; szrAcrH'orr,` or sourir GRANGE, NEW aEnsEm-AssIeNort, BY MnsNn As'- .siGNMnNT`s, To coMBUs'rIoN UTILITIEsooRroRATIoN; oFNnw YORK, N; Y., A

CORPORATION or MAINE.

nIscHAReE MECHANISM.

Application filed November 24; 1924. seriai'No. 751,886.

This invention relates to discharge mechanisms, and-more particularly to adischarge mechanism for removlngcolre and ash from 'gasgenerators ofthe shaft type.

Many types-of discharge mechanisms have beendeveloped for supportingv fuel in a column in gas generators of the shaft type and'for removing' ash and'unconsumed fuel periodicallyor continuously from the bottom of the column at rates which can be varied to secureV uniform carbonization and/or gasification of the fuel during its passageA through the shaft. Some difficulties .have been experienced in designing apparatus which will accomplish these results andwhich will atfthe same time brealz'- up the compact masses of hard clinlrer which tend to buildup in the lower portion of the shaft as the result of high temperatures maintained in the generator and'y of the great weight ofthe superimposed column of fuel.-

In'the type of shaft generator known as the Doherty gasshellV fuel is passed continuously downward in a' c'c` lumnv through the shaft and'is gasified by a blast of air or other combustion supporting gas introducedV axially or peripherally of the mid portion of the" column. Such generators are gen"- erally of large fuel treating capacity, and the'fuel'bed has such a large cross-section that a major portionof the combustion supporting gases are decomposed by react-ion with the carbon of thefuel before they can penetrate into the sectionV ofthe fuel bedl farthest removed from the gas inlets', i. e., combustion takes place more rapidly in those sections ofthe charge nearest the gas inlets.

Accordingly, another problem which arises in the operation of such generators is that widely differenti concentrations of ash and unconsumed fuel form inl the axial and peripheralsections of the high'temperature vgasification Zone. If the fuel charge isadvanced at a' uniform rate through the inner or axial and theouter or peripheral sections of the shaft some of theufuel will be discharged before it is consumed and/or the gas making capacity of thegenerator will be reduced;v

Some ldischarge mechanisms for removing coke and ash from gas generators of the shaft type'have been sodesi'gned that if the column'of fuel in the shaft is blasted from the periphery toward the center the discharge of fuel from the base of the column by the mechanism is arranged to be more rapid` at the periphery than at the center. On the other hand, if the fuel isV blasted from the center toward the periphery, the discharglng mechanism is arranged to pro# vide a more rapid movement of the fuel in the center'of the column than at the peripheryV of the column.

provide a discharge of fuel of uniform ash content, andato overcome the tendencyfor the' ash and fuel to form largeclink'ers at and below the point where the heat is concentrated.` Moreover, the discharge mechanisms which have been used heretofore generally include parts which move in a hori- Zontal' plane at the bottom of the fuel column. Vith such a motion the fuel is not agitated for any considerable distance above the mechanism and therefore the fuel has an opportunity to form large clinkers which build up on stationary parts of the discharge mechanism and obstruct the. passage of fuel through the shaft. As'any of these large clinlrers approach the movable parts it is sometimes quite difficult to break them up into sufficiently fine condition so as to pass throughthe discharge mechanism. Furthermore7 the discharge mechanisms above re# ferred to are not welladapted for advancing.

fuel atv a uniform rate through both the axial and the peripheralsectionsY of the column in generators wherein the fuel is treated by both a central blast and a peripheral blast.

The primary object of the present invention is to provide a discharge mechanism for shaft generators by which fuel may be advanced'continuously in a column through the shaft and thoroughly agitated throughout the full crosssections of lthe lower portion of the shaft to prevent the buildingup of masses of clinher.

Accordingly on-e feature of the invention contemplates'V the provision of a. number of independently movable and stationary elements mounted in the'lower portion of the shaft in vertically separate horizontal planes and so arranged that the upper element can be rocked upy and down in a substantiallyY vertical path to keep fuel in the lower portion of the shaft in a state of turbulent These designs of fuel discharging mechanisms are intended" to agitation, while other movable elements can be reciprocated through separate paths which in combination traverse substantially the whole cross-sectional area of the shaft.

Another object of the invention is to provide a fuel discharging mechanism for shaft generators by which fuel may be supported in a column in the shaft and advanced through axial and peripheral sections of the column at variable rates to counterbalance the ash concentration effect induced by introducing air axially or peripherally of the column. Y f

To accomplish this object another feature of the invention contemplates the arrangement of the several groups of movably mounted and stationary fuel supporting and discharging elements in two main groups, the elements of one group being mounted in the central axis and those of the other about the inner periphery of the lower portion of the shaft; the division of the downwardly moving column of fuel into axial and peripheral channelsr before it reaches the chief fuel supporting` elements of the discharge mechanism; and the operation of the movable elements at variable rates and through separate paths to remove uniform concentrations of ash and unconsumed fuel from the lower cross section of the column.

Another object of the invention is to provide a discharge mechanism for shaft generators by which fuel can be advanced at uniform or variable rates through axial and peripheral sections of the shaft and by which variable degrees of agitation can be imparted to fuel in the lowei` portion of the shaft.

To accomplish this object another feature of the invention contemplates separate control of the length of stroke and of the rate of movement of the driving mechanism of each of the axially and peripherally mounted movable elements of the discharge mechanism independently of each of the others, so that the movable elements can be displaced at uniform or variable rates through paths of uniform or variable length.

l'lfith these and other objects in view the 'ivention consists of the discharge mechanism hereinafter described and particularly defined in the claims.

The various features of the invention are shown in the accompanying drawings, in which Fig. 1 illustrates in vertical elevation, partly in section, a gas generator ofthe shaft type equipped with a coke discharging` mechanism which embodies the preferred form of the invention;

Fig. 2 is a plan view of the lower part of the discharge mechanism taken on the section line 2 2 of Fig. 1;

Fig. 3 is a sectional elevation of the discharge mechanism, taken on the line 3-3 of Fig. 2;

Fig. l is a sectional elevation of the upper ring fuel agitating element of the discharge mechanism, illustrating the manner in which it is rockedup and down; and

F 5 is a detailed elevation of one of the hydraulic engines by which the ring element is rocked.

The shaft generator illustrated in Fig. l of the accompanying drawings comprises an pright cylindrical shell l0 with a refrac- Y tory lining into which fuel is fed intermit tently or continuously through a charging neck 12. The fuel. is supported in a column in the generator, and as it advances downwardly it passes through an annular heating and distilling zone 14 in the upper part 0f the shaft wherein it is gradually heated and carbonized by an upwardly flowing current of hot gases. From the heating and distilling Zone the fuel passes into a high temperature gasification Zone 16 in the central part of the shaft wherein a part or all of the coke product of the carbonization is burned by a blast of combustion supporting gases introduced into the shaft either through a conduit 1S and a central blast inlet 20, or through a conduit 22, a bustle pipe 241e, and circumferential nostrils 26. lfVhen the axial inlet 2() is used for blasting part or all of the exhaust blast gases are withdrawn from the shaft through the circumferential nostrils 26. lhen the blast gases are introduced through the circumferenti-al nostrils 26 part or all of the exhaust blast gases are removed through the central inlet 20. Any exhaust blast gases that do not go through nostrils 26 or inlet 2O during these periods of air blasting are drawn upwardly through zone 14 to heat and carbonize fresh fuel, and are then removed from the top of the shaft. Any coke remaining after this treatment together with the ash formed by combustion of the fuel passes downwardly through a cooling zone 28 in the lower portion of the shaft and is gradually cooled and quenched by contact with steam or other heat transferring gas. rfhe ash and/or coke are removed in small portions from the bottom of the column by a discharging apparatus which also serves to support the fuel in a column and to agitate the fuel in the lower portion of the shaft.

The coke and ash removed from the bottom of the column by the discharge mechanism drops into a refractory lined hopper 30 which comprises the bottom of the shell, and from hopper 30 a portion is periodically removed through a sealed discharge chamber A heat transferring medium, preferably steam or water, is introduced into the generator through pipes or hollow support rods 3e, with the particular object of cool Vbrackets inl the design illustrated.-

trol temperatures in the gas making Zone o'fy the fuel column. The pipe 34 conducts the water (or other cooling medium) upwardly past the fuel supporting elements of the dis; charge mechanism and into hollow distrib uting arms or brackets 35. These distributing brackets serve likewise as supports for fuel guides and screens and for other staL tionary members of 'the discharge mechanism. The cooling water passes through brackets 35 (there being three of these See Figs. 2 ande) into the hollowcores of two ringshaped fuel'screens 3G andl 37, wherein the water is vaporized by heat transferred;

through the walls ofthe screen from the surrounding` fuel. The steam thus produced enters the fuel in the lower sections of the column through small annular nozzles or passed upwardly through the upper portion of the column to carbonize andpreheat the fuel, and the mixture of thesegases with the volatile products of the fuel and the heat transferring gas is drawn offl through a rich gas outletll() in the top of the shaft. The waste blast' gases from water gas manufacture and partof the Vsimilar lean gases of producer gas manufacture are withdrawn either through the aX-ial inlet 20'and con'- duit 1S or through the peripheral nostrils' QGv aud bustle pipe 2lidepending on whether the fuel is treated to a peripheral or au axial blast, and arepreferably voonducted through conduits 42 and hotvalves Llll-f into waste heat boilers 46 where their fensible heat is abstracted and utilizedV in generating steam. The cool waste blast or lean gases may then be preferablypassed through conduits 4:8 into preheaters or re-Y generators (not shown) where they can be buruezl and' their heat of combustion recovered and utilized in preheatingblast airl andA in superheating steam.

The discharging device serves to support the column of coal, coke, andash in the generator, to thoroughly agitate the fuel throughout the cross sectional area of1 the lower portion of the column, and to remove coke and ash periodically or vcontinuously from axial and peripheral sectionsv of'n the bottom f ofthe column at variable" or' unii'ori rates; It is made up ofsixseparatefsets of' movable and* stationary elements whichV are" positioned-inthe lower portion of'the shaftk inltwo main groups, oneof-whichis :mounted 70 axially of? the shaftA and the other mounted peripherally ofi' the shaft.- Above the Inovable andy stationary supporting e=lements mounted a movable agit'ating"r ring SOWlIiehis positioned centrally of: the shaftz 'Phe 75' fuelin theVV lower portion off the c'o'lunfinfisy thoroughly agitated' by an-J up-and-devintrockingv motion which isf impartedf toA thisy ring structure,4 and being positioned above the T` other elementsv of themeclianism the ring'fo alsoserves tojdividel the? lower por'tionlof' the downwardly moving column offuelinto' two streams,`=one of which passes'throughits? centralf core 52 while the other is=defieetedl into an" annular" passage" ori` channel libeiA 85 tweenl its outer"rn'r and the inner? wall-E of4 the shaft.

The column ofv fuel is? supported-in-v th'el shaft chiefly by acentralstationaryplate56'i and by'. a number'of radially arrangedfnov U0k able platforms 58` and stationary tables 60."v The plate 5G lies directly beneath-the agil' tating ring" and is vertically spaced there*-v from', and thev area of its'upper surface-isi p sufficient to support'positively' anyl fuel iii-95 the axial portiono'f the' column andi in-tlief core 52 ofthe ring structure".` A scraper 62,2 which is m'ovably mountedi on the upper' surface of? the plate 56`l and is" oscillated' back? and forth thereon, grad'uanypushesashif 100' and coke toward andl over-thelouterfedgesofi the plate. The ashA andr unbiiri'iedIV cokeff the peripheral seetion'fof the ohargei'sgradl" ually pushedv into the annular@channelV 541 and onto radially" arTrz'nifged plat'frms 5891053 and` tables 60 by the'rockingl' motin o'f Atheagitating ringv and thel weight"4 of?! th'e o'verlying` column" of' fueleV Y The platforms 58 and tables 60la`refn1'ount'f ed belo'wf the outerfedgelof the.` ringstruc- H0" tureand have theirv outerf edges overlapjgedit by the inner lining of' the: Siler their" inner' edges overiap'ped'by theoutroifl the '-ring. TheV platformsa'nd-tables'aretdis' posed alternately about theperiplieral space" U5y betweefflv ring 50.1 and the" inner Wall Ofi the shaft, (seevFig. 2) and the combined areaI ofv v their upper" surfaces issufii'cient tev positively supportV fuel inl the` peripheral seei tions of the shaft' and inthe annular p'as-V 120" sage or channel 543 Ash and unconsunied' fuel supported onthe'u'ppe'r surfa'ees-o'fithef peripheral tables isi displaced at" interyalsi over their edges';` by plows"` ori scrape-rs 64;

3l); while the rest ispush'ed o`n't`o""the'moifir n53 able platforms 58. The platforms 58 are reciprocated back and forth in horizontal paths which extend radially of the shaft axis, and by this motion coke and ash is discharged atvintervals over the front edges of the platforms and falls into hopper 80.

The upper element or agitating rings 50 (see Fig. 8) is built about a frame 66 of triangular cross section, and this frame is supported by two circular I-beams 68. The I-beams in turn rest on knees A70 of three hollow thrust caps 72, and each of the thrust caps rests loosely on and registers with thel top of one of three supporting stands 74. rlhe long upper side of the frame 66 carries a truncated-cone-shaped fuel bea ing surface 76 which is faced with refractory. ,A refractory faced depending cylindrical apron 78 hangs from the short side of the frame and forms the axial fuel passage or core 52 of the agitating ring. Another depending refractory faced. apron 80 is hung from the outer corner of frame and forms with the interior lining of the shell the annular fuel passage 54. The stands 74 support the hollow distributing braclrets for the cooling medium, previously described, and in addition to the hollow ringshaped `fuel guards 36 and 87 these brackets also support a cylindrical fuel screen 82 on the inner side of apron 80 and an inner depending cylindrical screen 84 immediately beneath apron 78. Screens 82 and 84 serve with the water vaporizing screens 36 and 37 to 4protect the lower portion of the agitating ring from abrasion and from clogging up with fuel, ash and clinker, and at the same time they serve as guiding channels through which fuel which has passed axial core 52 and annular passage 54 is directed in its downward passage onto the supporting surfaces of the centrally mounted plate 56 and the radially arranged platforms 58 and tables 60. n f

The stationary peripheral tables have horizontal triangular shaped fuel supporting surfaces, (see Fig. 2). Each of these tables lies between adjacent edges of two of the movable platforms 58, and the combined surface area of the tables is such that any fuel passing through annular passage 54 which does not flow onto platforms 58 is positively supported on the surfaces of the tables. A peripheral flat arch 86, (see Fig. 3) forms an enlargement or chamber 88 in the cross sectional area of the shaft adjacent the tables 60, and the outer edge or base of each table extends into this chamber a sufficient distance so that the fuel and ash expanding from the passage 54 will stand on its natural Vangle of repose without falling over the tables7 outer edges except when positively displaced by plow 64. The depth ofthe enlargement 88 is sufficient to leave a V spaceor channel 90 between the outer edge of each table and the inner lining of the enlargement through which fuel which is pushed over the outer edge of the table by the plow 64 can drop into hopper 30. Each of the tables 60 is supported by columns 92, and the inner short edge of every other table is also supported by brackets 93 on the stands .74. The inner edge or apex of each of these tables extends radially of the shafta suliicient distance so that the agitating ring 50 overlaps it, and the fuel which has passed through annular passage 54 and the apron of the ring structure is therefore positively supported on the surface of the tables 60 and on the movable platforms 58 as it expands on its natural angle of repose.

The movable platforms 58 lill the rectangular spaces which lie between the'edges of adjacent tables 60. The fuel supporting surface of each platform has a rectangular shape and lies in a plane slightly lower than the fuel supporting surface of tables 60, (see Fig. 3), so that the Scrapers 64 can reciprocate across the surfaces of the tables without obstruction. Each platform is supported on trucks 94, the wheels of which engage tracks 96 which extend radially of the shaft axis (Fig. 2).

The driving mechanisms by which the several movably mounted elements of the discharge mechanism are operated are all situated on the outside of the shell where they can be easily reached without interfering with operations in the interior of the shell. The mechanism by which the upper element or yagitating ring 50 of the discharge mechanism is rocked up and down consists of three pneumatic or hydraulic engines 98 mounted on a platform 100 beneath the hopper 80. Each of the engines 98 rests on the platform with its major axis directly beneath one of the stands 74. The stands 74 are supported by and disposed at regular intervals about the upper surface of the axially mounted plate 56 (see Fig. 2), and the top of each stand is drilled with a hole which registers with another hole in the base of the corresponding hollow thrust cap 72 (see Fig. 4). The hole through the top of each stand 7 4 serves as a guide bearing for a piston rod 102 which is attached to the piston 104 of the corresponding engine 98. The inner bearing face 106 of each of the caps 7 2 is rounded and lined with smooth bearing` metal, so that it offers a minimum frictional resistance to any side thrust motion of the rounded end of the corresponding piston rod. Each of the piston rods 102 is vertical and enters the base of the shell through a packing gland 108, and each rod is protected by a casing 110 from the abrasive and corrosive action of the fuel and gases in the bottom of hopper 30. The piston 104 of each engine is hollow and open at the lower end, as are also the corresponding piston rods 102 (see Fig. 5) and in operation each of the pistons is actuated b y the admission of water, air or other fluid medium under pressure into the cylinder casing through intakes 112. The actuating fluid, preferably water, circulates through the core of the piston red and serves as a cooling medium therefor, and the rate at which it is admitted and exhausted into and from the cylinder casing through intakes 112 governs the speed'at which the engine operates. Each of the engines 98 operates on an alternate cycle with each of the others. On the forward stroke of each engine the upper closed end of its piston rod bears against the face 10G of the corresponding thrust cap and raises the agitating ring above the top of the corresponding stand 74, but since at this time the other two engines are not operating on their upward stroke, one ofthe other thrust caps will always rest on the top of its corresponding stand. Consequently, the ring will be tipped on the up stroke of each engine, and as the engines operate on alternate cycles the motion imparted to the agitating ring will be a rocking up-and-down motion (see Fig. 4). This rocking motion keeps the fuel above the ring structure in a. turbulent state of agitation. The degree of agitation is controlled by varying the speed at which the engines operate and by increasing or decreasing the length of their stroke. Wings 114-, (see Fig. 5), are cast integral with the cylinder casing of each engine, and each of the wings is drilled for bolts 116 which pass through a check-yoke 118. This checkyoke straddles the piston rod and by means of nuts 120 the lengths of the bolts are adjusted to draw the check-yoke closer or move it farther away from the upper end of the cylinder casing. The check yoke acts as a bufferplatc for the upper closed end of the piston, and by varying the position of the yoke with respect to its distance from the cylinder casing the length of the stroke of each piston may be readily adjusted to meet varying conditions of operation. The length yof the stroke of each piston governs the distance through which the agitating ring is raised above the top of the corresponding stand '.74 during the up-stroke of the engine.

The driving mechanism which operates the scraper element ('32 by which the rate of advance of fuel through the axial portion of the shaft is governed comprises three hydraulic or pneumatic engines 122 (see Fig. Q) mounted on brackets 12st around the periphery of the outside of the shell 10. Three crank pins 126 are set in the frame of the scraper at regular intervals about its ciru cumference, and to each crank pin is attached one end of a radially extending crank arm 128. Each of these crank arms is connected at its opposite end by a loosepin joint 130 to piston rod 132 of the Correspondins driving .enenewaeh pstonrod .eateries the Shell through a packing gland f lfin ,the shell lining- The 'engines '122 areerefafes on alternate cycles, i.V e., while oneis onta forward stroke one of the others is on a back stroke, so that the scraper is continually oscillated Iin a circularor oval path across the surface of plate 56 and some ofthefuelsup.- ported on the surface ofthe plate is een: tinually forced over Vitsouter edge into'hopper 30. The length ofthe stroke of .each of these engines can be adjusted lindepeiul.- ently of that of each of the others, and-the length of its stroke and the rate at which each engine operates governs `the rate at which fuel is advanced through the ,axial portion of the generator and discharged over the @dse Of plate 56- ,lhfe Scraper ,is heller', and is waterooled by a Spray .135 which plays on its interior through an axialpp en-A 136 in the center of plate `5.6.

The driving mechanisms by which plat-A forms 58 are reciprocated ,comprise ,pneumatic or hydraulic engines 138 -Vdisposed radially of the shaft on brackets-which are placed outside the shell lining. vEach platform has its own driving engine, andeach of the engines has a hollow-open-e1 ldedpiston, similar in design to thefpistonspof 1eni gines 98, which is connected loy a piston rod 140 to the correspondingplatform. On the forward stroke of the pistonthe platform is advancedto its forward position, at which time fuel in the peripheral portion of the charge and in the annular passagev Lis positively supported on its surface. vOn the back stroke of the piston, however, the platferin is withdrawn, leaving an opening ,1&2 (see Fig. 2) between its inner edge and the outer edge of the l,plate 5,6, through which fuel drops into hopper 30. Depending on the length of the pistonstroke .and on the nate at which it is reciprocated variable amounts of fuelcan be discharged from theannular space 5,4 over the front edges ofthe platforms 58, ,and accordingly Vfuel can be .advanced downwardly through lthe peripheral sections of the shaft at a controlled rate which may be yfaster or slower than therate at which fuel is advancing through vthe axial portion of the shaft. The platforms may be reciprocated eithercnthe `samer on alternate cycles. A -boX-like offset 144 is built into the wall of the shaft behind each platform, and each .box .has an-.area large enough so thatthe corresponding platform can venter it during the back stroke of the driving engine.

The plows 64 are reciprocated by pneumatic or hydraulic engines 146 `which are mounted about the external V`periphery -of5the shaft. Each of the Scrapers is hollowv'and water cooled and is attached by watercooled connecting rods v1118 to a yoke 150, Which-in turn straddleslthepiston,rod `152 of theeor.-

responding engine. The position of the yoke 150 with respect t0 lits distance from the end of the cylinder casing is adjustable by means of nuts 154 on the connecting rods, so that the length of the stroke of the piston can be varied. The .speed at which the engines 146 are operated and the length of the stroke of the scrapers 64 both being variable, it is readily appar-ent that the rate at which fuel is passed downwardly through the peripheral portion of the shaft and pushed over the edges of table 60 is easily regulated. n The discharge mechanism is supported in the shaft by girders 156, each of which is preferably provided with expansion seats and is supported by the same columns which support the generator shaft. Plate 56 rests directly on these girders, while the other elements of the discharge mechanism are supported at various 'distances above the girders by stands 74, columns 92 and by trucks 94, as previouslyvmentioned.

T he hollow support rods 84 enter the ash hopper 80 through stufhng boxes 158 and are all connected to a manifold 160 positioned on the outside of the generator. A pipe 162 connects this manifold to a water storage tank 164 (see Fig 1). A piston rod extension 166 passes through the cylinder head f (of one of the driving engines 138 of platforms 58, and is connected by a pin to one arm of the bell crank 16S. The other arm of the bell crank is connected through a rod 170 to one Varm of a bell crank 172. The shaft of the bell crank 172 is supported by a bearing and stuffing box in the side wall of tank 164 and the end of the shaft which extends into the tank is 'attached by another arm through a pin and loose sleeve joint 17 8 to the upper end of a vertical rod 174. Rod 174 either comprises, or is connected to, the stem of a large float valve 176 having its seat in the base of the tank at the inlet of pipe 162. By means of these various links the motion ofI engine 138 and platform 158 is transmitted to the stem of valve 17 6 and the valve is lifted off its seat on each backward or outward stroke of the engine. By means of the sliding pin joint 173, the engine may complete its forward stroke without closing the valve, that is the valve 176 will remain open after the platform 58 has again moved into its forward position. The valve 176 is closed and a fresh charge of water is simultaneously admitted to the tank through a water inlet 177 by means of the action of float 178, acting through an auxiliary tripping mechanism and links similar to those used in the rcommon type of toilet flush tanks. A regulated volume of water is admitted to tank 164 through inlet 177 each time the flush tank mechanism operates, and each time the platform 58 is withdrawn from its forward position into box 144 the valve 176 at the inlet of pipe 162 is unseated and the tank full of water passes through manifold 160 and rods 34 into the hollow fuel screens 36 and 37 and after its vaporization therein the steam formed enters the base of the fuel column through the circumferential nozzles 88. By this arrangement the admission of water into the base of the fuel column in shaft 10 is timed to correspond with the periodic movements of the platforms 58 of the discharge mechanism. Vhile the admission of water vapor to the base of the fuel column has been described and illustrated as controlled by the operation of one of the driving engines 188, such admission of water need not necessarily be controlled by any particular engine 188, and the admission of water may be made dependent on the operation of one of the drivingl engines 146 of plows 164 without departing from the spirit of the invention. Likewise the use of cooling water is not necessarily limited to those elements of the cooling mechanism which have been described and illustrated as water cooled, but this use may be extended to include elements in which no provision for water cooling has been illustrated or particularly described. Thus for example the driving mechanisms and connections for Scrapers 62, and the fuel supporting plates of tables 60 and of movable platforms 58 may be designed and equipped for cooling by a positive circulation of water therethrough.

The number of elements comprising the discharge mechanism may be increased or diminished without departing materially from the true scope of the invention; nor is the manner in which the several elements are arranged within the generator material, so long as the number of elements chosen and the manner in which they are disposed and operated will ca'rry out the objects outlined above. rlfhe chief functions to be performed by a discharge mechanism coming within the scope of the invention arefirst,-to thoroughly agitato the fuel throughout the lower portion of the generator so as to prevent its obstruction by n1as ses of clinker; and-second,-to advance fuel either uniformly or at variable rates through the axial and peripheral sections of the generatorl so as to discharge substantially uniform concentrations r4of ash and unconsumed fuel from each cross section of the lower portion of the shaft.

One of the principal advantages obtained by using the preferred form of discharge mechanism described above is that each of the stationary elements has a movable elenent mounted thereon which is reciprocated or oscillated across its face at such frequent intervals as to afford no opportunity for clinker to amass and build up thereon. Another advantage is that each of the movable elements of the above mechanism is actuatlil) k..1,rssa4si lresult of this control. substantially uniform concentrations ofv ash and unburned fuel can always be discharged from the yentire cross section of the lower portion of the `columnin the generator, no -matter what mode of airrblasting is used in the high tempera-ture Zone. Another advantage obtained `by agitating the lower portion of the fuel column is that the Vcharge/is .kept in an open and porous condition with' the result lthat the heat transferring gases introduced throughthe vaporizing elements of the dis 'charge mechanism. can distribute themselves uniformly through the fuel throughout the cross section of the charge.

The arrangement whereby water, steam or other cooling medium can be introduced into the ylower portion of the fuel column Vconstitutes one of, the yadvantageous features of the present apparatus. Thus by this .arrangement the surfaces of the fuel .guides andscreens directly exposed to the hot fuel -in the'lower portion of the shaft can be-water-cooled, and the steam formed 'by a v-aporization of the water in these screens can ibe .admitted directly into the fuel at the base vof the column above -and out `of contact with thefmetal `portions of ithe discharge mechanism.

A shaft generator equipped with this preferred form of discharge mechanism can be opeiated'with axial air blasting, with peripheral airiblasting, or with both axial land peripheral air blasting with equal facility, since `the elements of the mechanism are arranged in two mainv groups, one in lthe axial andthe other in the peripheral sec tion of the shaft, and the rate at whichthe movable elements of each group are operated can be vvaried to pass uniform or variable volumes of .fuel through the axial and peripheral channels 52and 54.

The preferred form of theinvention having been thus described, what is claimed as new is:

`1. A discharging device comprising a number of movable andstationary elementsv Voverlapping each other and mounted in vertically spacedgroups, means for moving an upper axially mounted element through -a vertical path, Vand separate means forfmoving other axially and peripherally mounted movable elements in horizontal paths.

21A Adischarging device compri-sing a number of Ygroups of stationary and movably `-i'nountfed elements 'forming in com.-` "liination a lcomplete 'closure-for 'a shaft and .arranged `in vertically .separated ihorizontal planes,;.veach .stationary .element having a .movable element mounted on its upper 4supporting .surface :to discharge fuel over -its edge and to prevent .the building up of masses oficlinker thereon.

3. A .discharging mechanism comprising a .number yof vertically spaced groups of .stationary :and independently movable elements disposed axially :and radially about the central axis of a Vshaft Vand servin-gfin combination as a positive .support for .a column of imaterial, .and separate lmeans foroperating each of said -movably mounted elements independentlv of each -of the others. t. A discharging mechanism'arranged Ito support a column fo-f fuel in a-shaft, -to .agitate fuel throughout thelower .cross secition Vof .the column Yand y.to 'discharge unilform concentrations. of :ash and funconsumed fuel .from the bottom ofthe columncomprising :a number of stationary .and movably mounted elements disposed inthe central axis and `about the inner peripheryof the shaft .in two main groups, the axially mounted group comprisin-gian uppermovable agitating ring, a lower stationary-supporting plate, `and a movable V.scraper ymounted on the upper :surface of the :supporting plate, andthe peripherallymounted group :comprising a number of ymovable platforms, a numberof stationary tables, and a nurnber of movable plows mounted on the Vtop surfaces of the vstationarytables.

-5. A discharging mechanismarrangedto supportvmaterial in a column and A:to ad- Vance it through a shaft comprising astationary horizontal .plate vhaving its. center in the major axis of the shaft, a .movably mounted agit-ating ring .overlapping .said

i' plate and vertically spaced therefrom, said lring having its core in the :central-axis of vthe shaft, means for imparting a rocking motion to the agitating ring,.a.nd means for displacing material overthe edges ofthe plate.

=6. A discharging mechanism comprising astationary plate mounted Vwith :its :center in the majoraxis ofa shaft,.a disc-shaped scraper movably mounted on it'he top surface `of fthe plate, means for .oscillating the scraper yacross `the suria-ce .of :the plate :to displace material supported tliereon,a numiber of stationary tables-disposed at regular intervals about the inner periphery of the shaft and vertically spaced fromithe axially -mounted-plate, a plow movably mounted on `the1top surface of each lof the peripherall-y disposed tables, and `separate means l for `.ree ciprocating each of `:the plows vacross the surfaces vof the Atables .to displace material 'supported thereon.

417. A discharging mechanism comprising a 'ihoriZont-al stationary plate `mounted axially'fof ashaftfa number offstationary fta- Vbles supported at regular intervals about the inner periphery of the shaft and vertically spaced from the axially mounted plate, a number of movably mounted platforms disposed alternately With said periplierally supported tables about the inner periphery of the shaft and arranged to support material unsupported by said tables, means for at intervals displacing material over the edge of the axially mounted plate, separate means for at intervals displacing material over the edges of each of said peripherally supported tables, and separate -means for reciprocating each of the movably mourned platforms at intervals to permit Lmaterial to flow between the platforms and the axially mounted table.

S. A discharging mechanism comprising an upper movable agitating ring and a lower stationary plate mounted axially of a shaft in vertically separated horizontal planes, the surface area of said plate being sufficient to support material passing through the axial core of the ring, a series of stationary tables and a series of movable platforms mounted. peripherally of the -shaft and vertically spaced from the axially mounted plate and the agitating ring, the combined area of the top surfaces of said peripherally mounted tables and platforms being vsufiicient to positively support any material in the shaft not supported by the yaxially mounted plate and ring, and separate means for at intervals displacing material supported by each of said elements.

9. A discharging mechanism forming a complete closure for a shaft comprising an upper movable agitating ring and a lower stationary supporting plate mounted in the central axis of the shaft in vertically separated horizontal planes, a number of stationary supporting tables and a number of movably mounted plat-forms supported alternately betweenv the inner Wall of the shaft and the outer rims of the axially mounted ring and table, means for rocking `the'ring up and down,rmeans for reciprocating the platforms, means for at intervals displacing material supported by the axially mounted plate, means for at intervals displacing material supported by each of -the peripherally supported tables, and means for separately controlling the length of stroke andthe rate at which each of the said rocking, reciprocating and displacing means is actuate 10. A discharging mechanism comprising an agitating ring movably mounted in the central axis of a shaft, said ring having an axial. core and an outer rim spaced from the inner Wall' of the shaft, means for imparting a rocking motion to said ring to agitate material in the shaft and to deflect material through its core and through the peripheral channelfbetween its rim and the Wall of the shaft, means for supporting material passing through the core of the ring, means for supporting lmaterial passing through the peripheral channel, and separate means for causing material to flow past all said supporting means.

ll. A discharging device comprising an agitating ring and a stationary plate supported in the central axis of a shaft in vertically lseparated horizontal planes, a number of stationary tables and movably mounted platforms disposed alternately about the inner periphery of the shaft and having their outer edges overlapped by the inner Wall of the shaft and their inner edges overlapped by the outer rim of the agitating ring, a disc-shaped 'scraper movably mounted on said axially supported plate, a plovs7 movably mounted on the surface of each of said peripherally disposed tables, means for causing the ring to rock up and down, means for reciprocating said peripheral platform, means for oscillating said disc scraper, and means for reciprocating said plows.

l2. A discharging device comprising an agitating ring movably mounted in the major axis of a generator shaft on a number of supporting stands, a driving mechanism for the ring compri-sing a number of engines mounted directly beneath the supporting stands and outside the generator shell, an inverted open-end hollow piston in each engine, a vertical piston rod attached to each of said pistons and passing 'through the top of the corresponding supporting stand, a number of hollow thrust caps about the base of the ring structure, each cap having a rounded bearing surface to receive the upward thrust of a piston rod, means for controlling the rate at which each engine is actuated on an alternate cycle With each of the other engines to impart an up-and-down-rocking motion to the ring structure, and means for regulating the length of stroke of each engine.

13. A discharging mechanism comprising an agitating ring movably mounted in the central axis of a shaft on a number of supporting stands, said agitating ring having a refractory faced fuel supporting surface built in the shape of a truncated cone, a refractory faced cylindrical core, and a refractory faced cylindrical apron depending from its outer rim, means for at intervals raising4 the ring structure above one or more of its supporting stands to impart an up-and-doWn-rocking motion thereto, a stationary plate supported axially of the shaft Vbeneath and spaced from the agitating ring,

a number of stationary tables and movably mounted platforms supported alternately about the inner periphery of the shaft and serving in combination to support material not positively supported in the shaft by the axially mounted table and agitating ring, and means for at intervals discharging material over the edges of each of said tables and platforms.

14. A discharging mechanism comprising Ya movably mounted agitating element and a number' of stationary and movably mounted supporting and discharging elements positioned in close functional relationship in the lower portion of a shaft, separate driving mechanisms for imparting motion to each of said movably mounted elements, means for introducing a cooling medium into the driving means and movably mounted elements of the discharge mechanism, stationary screen-s adjacent the lower exposed portions of the agitating element, and means for introducing a cooling medium through the cores of said screens into the lower portion of a column of material immediately above said supporting means.

15. A. discharging mechanismcomprising a movably mounted agitating element and a number of stationary and movably mounted supporting and discharging elements arranged in vertically separated planes about the vertical aXis of a shaft, individual driving mechanisms for moving each of said movably mounted elements, means for introducing Water into the driving mechanisms and into the several elements of the discharge mechanism, means for introducing Water vapor from some oit' the elements of the discharge mechanism into the lower portion of a column of material in the shaft, and means for timing the periodic introduction of Water into the driving mechanisms and elements of the discharge mechanism to correspond with the periodic operation of the discharging elements.

In testimony whereof I aiix my signature.

GEORGE W. SAATHOFF. 

